1. Field of the Invention
The present invention relates to window glass for vehicles assembled to an elevation apparatus and other apparatuses and a method of producing the same.
2. Description of the Related Art
As a means of assembling vehicle window glasses, there is known a glass holder structure using adhesives.
In a glass holder structure of this kind, a polyacetal resin or a polybutylene terephthalate resin containing glass fibers is used for a glass holder for holding a glass for a vehicle, a primer is applied on the glass side and on the glass holder side, one-liquid urethane adhesive or one-liquid silicone adhesive not containing silane coupling agent and two-liquid blending silicone are used for adhering for assembling.
The glass holder structure is for adhering a glass and a glass holder, but glasses are generally considered a hard to adhere material
When assembling a vehicle window glass, it has been essential to use a primer for securing adhesive capability of the glass holder structure. The use of primer, however, requires a primer applying process, drying process and inspection process, and furthermore, a primer equipment and primer management. Also, means for improving the adhesive capability by using a primer requires a long time for the adhesives to set and a work for positioning a bracket requires a lot of efforts, which results in an increase in costs.
Furthermore, a work for applying the primer results in a bad working environment and deterioration in work efficiency due to the smell of the vaporized gas.
An object of the present invention is to provide a window glasses for vehicles capable of attaining a low production costs, high adhesive effects and a compact mounting members, and a method of producing the same.
To attain the above objects, according to the first aspect of the present invention, there is provided a vehicle window glass comprising a vehicle window glass; a glass holder having a groove in which said vehicle window glass is inserted to be held by being nipped made by a resin material of a natural grade of polybutylene terephthalate resin or a natural grade of polyethylene terephthalate resin, or a resin containing glass fibers in the natural grade of the polybutylene terephthalate resin or the natural grade of the polyethylene terephthalate resin; and one-liquid type urethane adhesive layer containing a silane coupling agent formed between the vehicle window glass of the groove of said glass holder and the glass holder.
Also, to attain the above object, according to the second aspect of the present invention, there is provided a method of producing a vehicle window glass by adhering with one-liquid type urethane adhesive layer containing a silane coupling agent a vehicle window glass and a glass holder having a groove in which said vehicle window glass is inserted to be held by being nipped made by a resin material of a natural grade of polybutylene terephthalate resin or a natural grade of polyethylene terephthalate resin, or a resin containing glass fibers in the natural grade of the polybutylene terephthalate resin or the natural grade of the polyethylene terephthalate resin.
On the surface of the vehicle window glass as one body to be adhered adsorbs water in the air wherein OH-group in the water and alkoxy-group in the silane coupling agent are bonded through a dehydrating condensation reaction.
The chemical structure of the polybutylene terephthalate resin or polyethylene terephthalate resin forming the glass holder as the other body to be adhered includes COO-group as a polar-group, thus, it is bonded with urethane bonding in the urethane sealant.
The one-liquid urethane sealant has isocyanate (NCO)-group at the end. After the isocyanate-group is bonded with water in the air, urea bonding is generated and hardened.
As a result, the vehicle window glass and the glass holder are rapidly and firmly adhered by the urethane sealant being added the silane coupling agent.
According to a vehicle window glass and a production method thereof of the present invention, it is possible to adhere between a vehicle glass and a glass holder furthermore firmly without using a glass primer nor a resin primer.
Also, a setting time of the adhesives, which has been long as a result of using a primer, can be made short. Accordingly, (1) abolition of primers on the glass side and on the resin side, (2) abolition of primer applying process, drying process, inspection process and equipments therefor, (3) abolition of primer management, (4) improvement of credibility in the market due to improvement in strength, (5) stabilization of quality and decrease in deficiency rate due to improvement of adhesive strength (particularly creep force) and reduction of unevenness in adhesive strength, (6) more compact members due to the improvement of adhesive strength, (7) reduction of adhering area due to an improvement of adhesive capability and (8) improvement of working environment by removing smells resulted from abolition of the primer applying process, can be attained and the economic effects is also large.